It's definitely a passion project. No one with any common sense would undertake it
I'll stick with the GALs. The objective is to use only chips that were available in 1985 and even the RAM chips I located are a little unusual, but they did exist in 1985 and Sir Clive talked about them for his new project. Finding them was a challenge though. Basically they are just fast SRAMs that are 1 bit wide and 64K bits long, but their timing makes them useful for video projects since they have separate read and write inputs.
A lot of people just use (and suggested using) the 6845 or 6545 that Hugo mentioned, but I think that's the last thing Clive Sinclair would have used. He was fixated on programmable logic ever since the zx80 and the 6845 can't do what just 2 GALs can do, which is generate all of the video timing and signals as well as bus-multiplex the video bus. I think he would have used a ULA, but then, they don't exist any more and so the only other chip he would have used was the PAL16v8 and PAL22v10 which were both common enough in 1985. Using a modern programmable logic chip would be like using a raspberry pi instead of a z80. I want to stick to what was available in 1985. Amstrad used 6845's but even they went with the custom logic for the Spectrum screen in later Sinclairs.
Our first K-mart appeared when I was around 12, so for me, the closest I had to a cafeteria when really young was Boans in Fremantle. It was a big place and like you, some times I got to go there, but Kmart was more interesting an by that time, I was old enough to find my own way there. What I was really missing was an electronics shop. The nearest serious shop was in Perth. When I was 13, a whole lot of us played hookey for a day and got onto a but to head into Perth to visit this "Dick Smith" place we had heard about that would sell us a floppy disk for about $10ish that we could use on the School Vector Graphics MZ. It was a long day and a bunch of 12/13 year olds unescorted roaming the city by ourselves on a school day probably raised a few eyebrows, but most of the teachers knew what we were up to and were more amazed that we were finding our own floppy disks to use on the school computer since they didn't have enough disks to share with us so we not only got caught, they let us get away with it and even encouraged us! It was probably the only geek priviledge we ever got and it caused enough trouble with the other student who got in trouble for playing hookey we were told to never do it again, which was a shame since we were already planning another trip to get more.
