Since the Theta unit is a Pioneer in reality a new laser should be available from Pioneer and I have a guy in Virginia that will do the repair for you. He does a good job and is reasonable. He does all of the laserdisc repairs for me. Another good place would be United Radio in New York. They are an excellant repair facility.
Rebuilt laser any good?
My Theta Data Basic II transport worked perfectly for 3.5 years after I got it but recently started skipping. The nice Theta guy says a laser rebuild runs about $400 and offers about 95% of the original performance. Search of the A-gon database shows others have already been here. Does anyone care to say how your repair results affected performance?