You're correct - this is a non-inverting hex buffer. Function, but NOT pin-compatible with a CMOS 4050. Here is where I found a 7407 locally: http://www.mcmelectronics.com/Search/search4-frame.jhtml?_DARGS=%2Fcommon%2F prodsearchform.jhtml MCM Electronics has 'em. They're $1.16 each in quantity of 1. Good luck with your project!