An FPGA conversion ASIC would be $35,000+ NRE, and that's pretty cheap. An FPGA is what, under $100 these days? The reason ASICs are cheap is because you sell thousands or millions of units to amortize the NRE cost.
I recall reading development was being done on a pretty beefy FPGA; one that would not be limited to emulating just the C65 (note the C65 was based on a 65CE02 16-bit CPU at ~4MHz, and not the 8-bit 6510, so quite a bit more demanding than a 6510 at ~1MHz).
I went searching for prices way back when I first started reading about the Mega65 project (I donated back then and got access to the core files, but didn't go through with buying an FPGA to try them on), and I think the FPGA in single-unit quantities was over $200. I may be misremembering, and I may have looked at the wrong vendors, though. But, I think they're not targeting a super low-end market for this project. Which, I think is reasonable. People with no money to spend will run an emulator.
So, I hope it won't be too expensive, but I won't flinch if it's a few hundred dollars, even though I picked up my current working C64 for under $50.
I imagine the FPGA alone, without the ancillary stuff will be somewhat cheaper (nope, I checked...not much cheaper...DigiKey has the Xylinx Artix-7 in single quantity for $256). I'm not an expert on these things, so maybe I'm looking at the wrong parts.
I just recall looking up what it would cost to run it today would cost, and thinking, "I'll just wait until they ship it all in a nice C65 style case".
It looks like they're going for an FPGA that has 512K+ of RAM directly on board. That's really expensive and I note that even the Altera stuff is in the same range of price. That's a poor design decision.
4Mb SRAMs are something like $10 with a 10nS access time.
I don't have a problem with 4 layer boards. It's not worth wasting the brainpower (and debugging time) anymore to route something with 2 layers when you can have great ground and power planes for a really marginal increase in cost.
The issue seems to be keeping all the RAM in the FPGA. That's pretty expensive.
ASIC: high tooling cost, lower unit cost
An FPGA conversion ASIC would be $35,000+ NRE, and that's pretty cheap. An FPGA is what, under $100 these days? The reason ASICs are cheap is because you sell thousands or millions of units to amortize the NRE cost.