about the rat you already have here is a link that will help you tell what you have
Sexing Rats
i have 15 snakes 17 as soon as it gets warm. right now i have 2 BP that eat med to large rats, 2 RTB that eat large, 3 RTB that eat meds, 2 RTB eats small, 1 GTP that eats small, 1 rat snake eats small, 1 burm that eats large rats to small bunnies, 2 retics that are on weaned but moving to small, and 1 retic that eats large to XL rats.
i was paying about 300 for rats and bunnies that lasted me 3 to 4 months, for my rat bedding and food i think i pay about 30 a month and right now im feeding 34 rats was more but i just put down about 12 in the last 2 weeks.7
this is what i use to see what size my rats are,
Pinkies: 1-4 days old 3.00-8.00g
Fuzzies:10-13 days old 9.00-19.00g
Pups: 14-18 day old 2.00-29.00g
Weaned: 21-25 days old 30.00-44.00g
Small: 26-32 days old 45.00-84.00g
Medium: 33-42 days old 85.00-174.0g
Large: 43-60 days old 175.00-274.00g
X Large: full adult size 275.00-374.00g
XXLarge: 375.00-475.00g
XXXLarge: 475.00-600.00g +
if you want to breed rats for only 2 snakes i say go for it you can always sell the ones you dont feed to your snakes. i will start out with 1 male and 1 or 2 females.