Your new rat girl sounds just precious..I am sure you are already in love with her and as you sound like a very patient, loving and caring rat and mouse mommy, I am sure your new girl rat will become very attached to you and love you right back! I would have had a hard time not wanting to save this poor girl from a possible bad fate, with the discount thing you mentioned and the lack of an eye. Poor baby. She was VERY lucky that you adopted her and I am sure she is grateful to you. I am so glad she has a safe home with you now.
(I also know how you feel...my husband and I just adopted two baby boy rats from a local shelter a month ago...they just turned 9 weeks old and we love them from head to toe!)
Yes, I would definitely advise getting her a female roommate. Rats are SO social and they really need the companionship. I know there are some instances where a rat just cannot get along with other rats, but this is a very rare exception. It is usually for rats with behavorial/territorial issues with other rats.
Since we don't know how she lost her eye, it could have been a variety of different things, and not just neccessarily a cagemate. From what I have been told on the forum, when introducing a new ratty to your girl, you can adopt a young female who is perhaps even younger than your new girl, as I am told rats have easier intros with a new friend who is a tad younger. If I have my information wrong, someone on the forum can correct me and help get my facts straight, ha ha!
Of course, this does not mean that you cannot get her a roommate who is her age! Just a general comment I have heard before on the forum. Since she is still young, I think you would do just fine with introductions with a new rat girl to keep her company.
I really think your new girl would feel more comfortable, safe, and very happy having another girl to cuddle with, feel secure with, and for all the things that rats love...grooming, sleeping and playing. And of course, two rats are just as easy to care for as one.
Oxbow lab blocks are great! I have heard that some rats do not like the taste but if your girl likes them, then that would be super. It is an excellent lab block. My other choice would of course be Harlan Teklad lab blocks that you can order online from various websites that sell lab blocks for rats. Mazuri lab blocks are okay if you need lab blocks right away, as they are sold in pet store chains but that would be a definite third choice. Just stay away from those rat seed mixes sold at pet stores. Not enough nutrition for a ratty and too much fattening filler junk in them.
As far as saltine crackers go...I have never fed my rats those so I am not sure if the salt is too much or if saltine pieces are okay? I usually tend to stick closer to whole grain type things and stay away from white flour type products so my rats can try to stick closer to healthy snacks. They LOVE plain Cheerios...an excellent treat, and small, so you can give them more of them.
Lil furries don't care how big or small the treat is...they just love getting a yummy treat from mom, so the smaller I keep the treat, the less guilty I feel if I give them some extras!
We also treat our boys with things like, small bits of whole wheat bread, uncooked spiral or macaroni pasta (keeps their teeth whittled down) plain rolled oats, either dry or with a bit of warm water to make it into a soft oatmeal mush, BABY FOOD is always a hit (our boys love Gerber Sweet Potato baby food and peas), Gerber baby Rice cereal, plain puffed rice, kashi, bits of whole wheat tortilla torn in little pieces, things like that.
And of course fresh fruit and veggies in small quantities (too many veggies and they can get the runny poop!) so we feed them little bits of things that they like, for instance, broccoli, bok choy, peas, a bit of banana, etc. You can find out what your girl likes or does not like by experimenting. I thought my boys would LOVE some carrot and apple and they said, "Nope, we don't like it!" So there ya go. You will find out what your girl loves.
Well, my fingers hurt from typing, so I will sign off for now! Hope this helped a bit? Can't wait to see pictures of your new sweetie pie!!