old Weathershield(?) sliding door mortise lock set

Hello,
I'd like to replace the handles and keyed lock set for my patio doors. They are two doors that slide to meet together with a mortise lock; it may be a Weathershield. The three handle holes are 4-5/8 apart. I would appreciate any replacement suggestions, and don't mind drilling new holes in the door if installation necessitates it. I am interested in either white or nickel finish. Thanks!