That happened to Kit when he was a puppy! His mouth looked really similar, he had his baby canine teeth at the same time as his adult teeth.
I got a quote from my vet for having them extracted and I think my vet charged something like $20 per tooth that needed to be pulled. Plus the cost of anesthesia and monitoring and pain meds, but I was already going to have to pay for all that because we were going to get Kit's teeth pulled during his neuter surgery to avoid having to put him under anethesia twice.
Buuut about a week before his surgery, I was playing with Kit with one of his toys and we where kind of having a little tug of war match and tugging/chewing on the toy made his retained baby teeth fall out.
I've heard that letting them chew on stuff can help loosen the teeth too.