If you are on a budget, FB marketplace or Craigslist. Shipping is going to add ~ $100 to the acquisition.
+100 Old school rigid frame MTBs are so adaptable.
Drop bar conversion, note handlebar height is slightly higher than saddle height (old rider, not so flexible), 1984 Trek:
fullsizeoutput_915 by
bill, on Flickr
Schwinn Sierra MTB, North Road handlebars:
fullsizeoutput_3d2 by
bill, on Flickr
1992 Trek 950 with trekking bars (simplest change by far):
trek 950 010 by
wrk101, on Flickr
Schwinn Cimarron Insanity:
Four of a Kind by
wrk101, on Flickr