I just started using Blur by Abine, which allows something similar. (Basically, you can fund prepaid cards to use on sites rather than giving out your real card

I just started using Blur by Abine, which allows something similar. (Basically, you can fund prepaid cards to use on sites rather than giving out your real card) not an outright endorsement. I haven't used them for long enough to give a definitive answer on if they're good, but it costs $40/year plus $2 for each "masked card". So far it's worked for me. I definitely agree no Dev should write their own gateway. There are great ones out there who are developed by people who are paid to do nothing but that.