Cheap and cheerful it's hard to beat a Garmin Etrex H for around $100 new
Batteries last a good 25 hours will get full reception sitting on the cockpit floor and being tiny easily fits in any nav or headset bag.
At the end of the day you should have learnt to navigate by DR in your CPL, and be aware of the different types of airspace around you. If you need more than a Bearing, Track, ETA and a Groundspeed to confirm what you should already know, what are you going to do when the unit switches off?
Garmin 96s, 495s, etc. are all nice to have, but hardly a MUST HAVE FOR FIRST JOB, especially for the price. Worth spending a tad more and getting one of the units that hooks up to a PC to enter new waypoints, displays a HSI, etc.