A good joystick for Clod

[bolox]

100K linear, 270° would be a standard pot. the type used in some joysticks do often have a reduced 'active' rotation of ~60 deg as you notice.

pretty much any 100k pot will work tho i usually look for at least 1/2 Watt rating and if its in the specs the projected number of rotations ~1000000 is good.

for a first project i'd suggest just getting cheapish pots(<£5) and a cheap plastic 'project box' to mount them in. if you are thinking of using one or more pots for trims (partic elev) i'd recommend finding a pot with 'multiturn' capability-5 or 10 turns is normal. these are around £10 each but the better sensitivity is worth it

good luck