It could also be a problem, that they are very hard to get tame when grown up, and can eat trough almost every thing.
When that is said, they are used for sniffing out landmines, and very easily trained... The best thing would be to find a breeder, and ask the breeder for a baby.
You could try and contact these people:
I'm not that happy about telling people to contact them, because they have an tendensy to just get loads of exotic mammals, don't do any real reserch, and then get a bunch of offspring, they can sell for profit.
On the other hand, I don't know/know of any other people, that might have and breed this animal.
Then there is this site:
Try looking around and asking about it.
They are called "Hamsterratten" in german, and you need to look for "nager" or "nagertiere" (rodent and rodent animal)
I'm not that good at german, but if you need help on some german sites, I might be able to help