I just got off the phone with L &L Electronics. You can't beat these guys. I hava a Mini 10 that was used for several years when I got it and now I have used it for several years. I sent it in because sometimes the volumn is not very loud. They completely refurbished the whole unit, re-tuned it and the bill came to $24.50. With the shipping it was $37.71. I have 2 Mini 10's and I bought them both used. I also have 2 transmitters made special for the eagle and they were $100 cheaper per transmitter than the ones that Marshall sells. Marshall does make nice good looking stuff, but, out of my price range.
I think one of my mini 10's is at least 10 years old and probably more. The other one I got about a year ago from a guy who bought it new in 2004. Hew was getting out of falconry and had used this receiver once or twice and I bought it for $400. It has the spring loaded yagi.