I am going to be purchasing a Omega Constellation from the early 1960's from a coworker who is a collector and I was wondering what i should be looking for. We negotiated a price and I believe it to be slightly high but I really like the watch so agreed to it. I know it is a champagne dial with date and has a bead and rice bracelet the dial has some minor patina that I think adds to its desirability. The condition is around 85%-90% with some very small scratches. According to him the watch is original (numbers match) including the crystal which he showed me has a small omega symbol in the center very hard to see but i could make it out. The one thing he said was that the gaskets are old and would eventually need to be replaced he said he took the back off and everything is very clean. I asked him to take some pictures of the movement and the caseback. He has mentioned he believes its a 561 movement. Please let me know if there is anything else I should look into. Also if someone could recommend a watchmaker to do the service somewhere around the Boston, MA area.