I know I asked this about you before. But why not at least get one kid? Out of all the posters on this site, you seem to be probably one of the more responsible potential parents. Yeah, you are in your 50s, but you can get the kid to college for sure before you expire.
Obviously you can go on Match.com and get some 30 something gal pretty quick.
I dunno, you really want to be 80 on your death bed and not have a kid giving you a high 5 before you move on?