I agree with previous poster, the first thing I thought of were the cloth diapers with snap closures. These are more difficult to get off then the velcro closures, however, little more difficult to get on - not hard, but if you have a squirmer it will take some getting used to. You can just get the cloth diaper covers that snap and put them over his disposable diapers. That way, you could use just 1 cover per day as opposed to the expense of stocking up on cloth at this point when he'll be out of diapers before long. The cover would not get messy, so you could just throw it in the wash with his clothes - no extra washing. Hope that helps. Good luck!
Here is a link to show you what I mean...
http://www.cloth-diaper.com/diaper_covers_wraps.3.0.0.0.htm
On this page, there is a pull on style and a snap style. You'll have to do more research to get the best price, I've never ordered from this site, but the page looked like a good example of different styles. If you have any questions about cloth, feel free to email me.