That bike looks pretty nice. You can take the foot straps off or just buy a different set of pedals. You can put some wider tires on the bike, but I can't tell how wide you could go. In your market I would think you would be able to find something on craigsliust.

Check this out. For $100 you could do a bunch to it and still be within your price range and those older frames usually took wider tires. In 100 postings I saw at least 3 road bikes that would be your size.

http://philadelphia.craigslist.org/bik/2359564712.html