JPK - Loose Pommel & Guard Question

[SolWarrior]

I bought a 1-1973 JPK off eBay for $30 shipped and it arrived last Saturday but didn't have time to inspect, clean & treat the sheath and leather handle 'til a couple days ago. Turns out the pommel and guard are a bit loose. Does anyone know if there's a quick fix to this? Here's three eBay photos & three after cleaning and treatment. Notice the crack on handle closed up pretty good.

Pommel type

I thought I'd put a little oil on the back end between washer and pommel and apparently over did it. May go away as with a sheath that accidentally got some oil spots and eventually spread out evenly.

[knife7knut]

Sounds like the leather handle has shrunk a bit. Not sure what you could use to swell it again without darkening the leather and perhaps inducing it to rot.Maybe someone with experience working leather will chime in.