Another way to ensure you always have proper sized prey items to feed, would be to buy a larger number of mice, feed them and let them get chubby, THEN feed them off.

That's what I do. I buy 250 at a time, feed off 75 or so in the beginning when I first get them, and by the second week I need to feed, they are much bigger and healthier, especially the males.

Even my adult females do fine on mice(some are over 2000g). Your small Spider male would have been fine on 2-3 small mice a week(or less). Even my adult males only get 2 mice every week to 2 weeks, maybe 3 if they have been in with a female.