So, here's the thing:

Recently the car started to make a slight knocking/tapping sound at idle. The sound went away as I pressed the clutch so I thought is must be clutch / trans related. I pulled the engine and it's definitely in the transmission. I verified this by rotating the transmission input shaft using an electric drill.

Here's a short clip about that:
https://youtu.be/2GAHxo7bhY4

Never dropped the clutch or did anything same kind of stupid but I cannot speak for the previous owner.

Could it be the input shaft bearing or something else? Doesn't sound a like bearing failure?

Car:
1999 WRX GC8 160kW (known as Impreza GT in Finland)
Trans code:
TY754VN1AB

Looks like I have a few options:

1. Repair the gearbox myself, cost estimate 200-400€

2. Switch to 5 speed Type r box with DCCD (ty754vb1ca). I can have the box, rear diff, axles and the DCCD controller for 1300€ (about 2000 AUD). I believe I would need R180 rear hubs and brakes but one option could be to use the "Suberdave R160 - R180 Hybrid Axle shafts". The clutch, trans & rear diff mounts are the same for all GC8's aren't they?

3. Do a 6 speed swap (not cheap!). 6 speeds go for 3000€ around here and that's not including all the other parts (clutch, slave cylinder, drive shaft, rear diff etc) And generally the parts are incredibly hard to find here. I could try to find a wreck car witch the right parts but that could take a long long time.

I'd like to hear your take on this. The future power goal is at least 350 WHP, currently at about 270. Fix the 5 spd and start saving for 6 spd? Is my power goal too much for any 5 speed anyway?

-Timo