Yeah, as above, the least important thing is the bike. How long a ago did you quit riding? At least you know your size and fit. Just get something used, something you can have now. You provide the speed, not the bike. You might be able to use the same fit as always. I'm 78 and still have a slammed -17° stem. When your good bike comes in, sell the used or, better, keep it as a spare. It's good to have a spare bike.