Doug Oade will only mod units that he originally sold. He has all the serial numbers recorded that he originally sold, so you don't have to have actually bought it from him, only have one that matches the serial numbers that he sold. If you don't have an Oade unit, then Busman is definitely your best option. PM Busman on this site. He does his mod work on new units (R4s now, not UA-5s) for Cascade Media (www.cascademedia.net), but since you would not be buying anything from them, I don't think it's best to try to contact him through their site.