Good news folks!
I tried both an MM74C14N, and a CD40106BCN in place of the SN74HC14N. Both are good between 3vdc to 15vdc, and both work fine. Between them and the 74HC14, I don't hear any difference at all, and functionality is the same. Maybe better. I think a get more of a difference between settings, but then again, I've been wearing the headphones on this thing for the last 3 days, so I might be getting PLL deaf by now. Also, I've cranked the voltage up to +/-12vdc. Everything works perfect.
I recommend going with this IC, unless you wish to be uber-precise where the clone is concerned. Personally, I'm leaving the MM74C14 in there, and running it at 12vdc. One of those moments of folly where I decide to stray from the original.
I was at ABRA Electronics today, and I came across this 12vac 800ma power adapter;
http://www.abra-electronics.com/products/AC%252d12800%252d2.1-Wall-Adapter-12VAC-800mA-%252d2.1mm.html. I bought one, because the in-store price was $2.99. Yeah, you read right... $2.99! With the right plug and everything. I tried it tonight, and it works fine.
Also, I tried a 2.2M resistor for R6. I dunno, I might be having sonic hallucinations, but it didn't sound as good to my ears. I put the 1M back in. Here's a video I shot, this is with the 2.2M resistor, and the SN74HC14N chip. It's a mishmash of knob twiddling, and general sonic mayhem, but there's some decent stuff in there as well. I'll do another one with the stock 1M in R6, and the MM74C14N.
[youtube]http://www.youtube.com/watch?v=jwldgSVa9nc[/youtube]