I've done that! The original campy 35/36T 116bcd rings are quite hard to find, and are PRICEY when they come up. I don't know if 48s or 50s were even made.
Some googling later I found that Miche makes compatible rings (35 to 48T) for the "Young" crankset, a crank for kids that come in short lengths. I found some rings on eBay.it, but most Miche distributors should be able to get some.
here is a
pic. I only could find a 36-46T set. And I had to file the shoulders of the ring's seat to match the spiders of the crank. More
here.
Thanks for the info. You did a great job adapting the Miche rings. Do you use the standard Victory front derailleur on this setup?