All I found was someone who had one for many years
A look at the HW45 .22 in action. I've had this pistol almost 10 years fired 1000's and 1000's of pellets never done any maintenance other than adding a drip of oil every few thousand pellets, adding a tiny bit of Vaseline to the seal and I think I cleaned the barrel a couple of times. The gun is an indestructible hunk of German steel and is very accurate but it's hold sensitive like any springer.
Usually the seal is around where you put the pellet and like a regular firearm you oil what ever moves to keep friction from eating the metal
Use vaseline sparingly because you might without knowing "diesel" your pellets and that will add more pressure to your gun (google pellet dieseling)
Personally I'd only use the oil for everything
I have had a few pellet guns and what's most important is to use a "non detergent oil" because it's detergent in most oils that will dry up and crack rubber and seals. That aside those guns are mostly maintenance free. If you want to clean the bore and rub the color off of it, it's up to you but it won't make it shoot any better or last longer
i don't have the diagram of your gun but google and youtube are your friend
You find that kind of oil in any place where they sell motor oil just look for "non detergent oil" on the bottle