OK if it was me I would check the filter with a magnet Se it the shiny parts are magnetic
And I would repair the filter ..there are how it is done here on the forum some quite pretty sheet metal work
by fex 5 Twins
Putting some miles on the machine for the evaluation If opening the engine more work is normal to do.
If inexperienced it can be causing more damage than do good replacing the parts inside. Depending current status
Need to take the engine out from the frame have tools and place to do it.
Not impossible ,,but I still feel getting some facts of the machine before tearing out and down Compression smoke
Slipping clutch gear shift rattling ?
I depends on the plan and finances with the extreme points Try to ride and not wrench or the other end wrench not ride.
New Filters is available I have bought parts from Kiel in many years Been pleased with that . Perhaps are cheaper and better out there. I believe much parts is the same as Mikes not all are pleased with
Freight and customs makes it more expensive get to Europe
https://www.xs650shop.de/en/crankcase/931/oil-filter-sump