I have bought a 555ELD last year and I´m pretty happy with the purchase. It was a good deal and looked virtually new. The 555 is the most advanced of all the 500-series cameras, with an even improved mirror mechanism and motor drive. They really go for much less money than a 501cm or 503cw, although they have all the benefits of these and then some. Must be only the weight and bulk that keeps people from buying...
1100$ sounds a bit high, I have seen many of these in the 800-1000$ range, but all depends on the shape.
The ELM might also be a good choice as long as it is significantly cheaper, but the 555ELD has many benefits that should be put in consideration:
acute matte D screen vs old screen, new style vs old style viewfinder. gliding mirror, more durable motor and mirror mechanism (not that the old ones were not durable!), and if you ever need it: digital back capability, TTL flashmeter, infrared remote control.
If you want to travel much and light however, I would rather opt for the 500CX or 500CM!