Think yourself lucky! My dad had an elite riviera when I was 14 which Henry on this forum found in a field. He has it and is doing a great job restoring it. Some great photos are on here and he may be able to tell you what he has spent so far.
In really good condition probably worth £5500 or so (others will disagree). Will never be economic but that is not really the point. Very few old cars would ever be restored on that basis. Yes it is rare, but for reasons that escape me, that does not mean it is worth a lot! Do you recall the registration mark ?
Buy it and store it !
Happy New Year !