GBK Breeder

I've seen something referred to as a Route 277 GBK. Do these have the same feeding issues? Visually they seem very similar to the GBK.

In GBK, locale specific breeding lines are very popular. The Route 277 just means that is the location where the parents or grandparents were collected originally. Different locales can have variations on their patterns - different width in bands, more red or more gray etc...
Any GBK hatchling could potentially be a difficult feeder. That is why it is recommended to get one a little older - not a fresh hatchling - and from a reputable breeder who can verify if they are eating mice already.

Nick, John of coloradocorns has some christmas mountain locale GBKs. He hasn't bred them yet, I think he might this year for the first time, or maybe next year.
Also, I will PM you contact info for a guy that does GBKs here in the Denver area.

I believe John Cherry of Cherrryville Farms still breeds them and has some great stock ... I personally have Thayeri, Corns, Black Milks, and Sonoran Gophers from him and all are top quality in my opinion.

Troy Hibbitts has a few locality GBK breeding programs.
http://www.thehibbitts.net/troy/field/alterna.htm
https://www.facebook.com/troy.hibbitts

I recently found this breeder as well: East Bay Vivarium

Thanks for all the info, with the pickiness of their eating I want to find a good line of healthy feeding snakes

Buy a yearling or darn well-started baby, would be my advice.