Other suitable GPS systems are from: Altus Metrum (TeleMega, TeleMetrum, TeleGPS), Missile Works (T3, RTx), Multitronix (Kate 1 & 2), Entacore (Aim Xtra), Big Red Bee (BRB 900) and Apogee (Simple GPS).
The Tile-like Bluetooth products are junk, I know. Stick with the larger rocket vendors. Do a search on this forum and you can find a comparison of altimeters some of which include GPS trackers built-in.