No spacer. These butt plates were made of a bakelite-like plastic and were prone to breaking and chipping. Try here: Vintage Gun Grips - Reproduction Pistol Grips, Buttplates and Grip Caps.. Anything you find will possibly require fitting.
Below is a shot of the butt plate you're looking for.

 

Model 1936 buttplate

OK, I'm baffled.

I've spent a long time looking on line for a replacement buttplate and screws for a Model 1936 and
there seems to be nothing available.

Many sites have buttplates for all the other models including the 336 but theres no mention of the model 1936 or Model 36.

The other replacements all seem to be a different size than needed for the 1936.

Why is there no replacements or is there a buttpad that will fit after some modification?

 

I have a model 36, 30-30 built in 1885 and I also cannot locate a correct butt plate. any answers out there?

 

I can pretty much guarantee you don't have a model 36 from 1885. You might want to check the barrel and see what you actually have.

 

Might try your local Gun show. That is if you have one . Lots of spare parts to be had.

 

The Model 36 butt plate is the same as on the 336 except no Marlin logo. In fact, the 36 butt plates were used on early 336's until the 36 butt plates were exhausted. I have a 336SC from 1948 which has a 36 butt plate on it. It too had a chip broken out at the heel of the butt plate. My 82 year old stock maker friend built a "dam" around the chip and filled the area in with black epoxy and finished it off to where even I can't tell where it was repaired. Try and find a plain black plastic butt plate and have it fitted to your Model 36.
358 Win