Well, I have ’62 & ’63 set-ups already rebuilt, ready for someone who might have wanted a quick turn around. For this car, I did take the turbine and by-pass housings, clean them up (were in great condition)and couple them up to the ready to go throttle body, carb, fuel filter and metering valve system. Also had a reconditioned air cleaner ready to go. So as you say, the timeline is quite short for this pictured system.
Yes, the fluid injection system filter can still be found. It is the ‘old style’ AC Delco GF61. They are on eBay from time to time for $20 to $60, depending on what the seller says it might fit. When they say ’57-’62 Corvette, the price is high, but they are all the same filter!