Man, I must have gotten right in at the tail end of Famicom to NES converters being super common & cheap.
I think it was about 6 years ago I got a few new manufactured ones like these for around $5 a pop:
and a classic HoneyBee style one and I didn't pay anything close to what the going rate is today...
...sheesh, eBay auctions going for close to $100??