never had any work done by Davis Slade but i would guess with shipping 2 ways and the parts and labor 175.00 to 250.00 and if he doesn't need the stock keep it for safety and wait till the first on the year, crazy time for shipping
now the 60 series rifle are not as complicated as the model 75's and with that could be cheaper
now this place Waffencenter Gotha has the best number of parts it will give you an idea of prices which are fair shipping sucks though
https://www.waffencenter-gotha.de/shop/DIANA:.:2.html?filter_id=274 the 65 is a fine rifle and you will enjoy it once rebuilt but do not shoot it anymore with damaged seals
http://mirrorzeta.altervista.org/Esplosi/Diana_65_esploso.gif learn all you can about the rifle is all i can say
https://forum.vintageairgunsgallery.com/post-war-diana-air-rifles/diana-model-65/ all i have but if you have a question i would try to help
mike in Washington states
