Nice update GK.
If you don't have and panal beaters near by you to get some from.
Just try spack filler.
Spack filler is just very fine plaster that is mixed with water to make a past, you normaly use it to fill hole's and cracks in the walls of house's.
You may find it a little porous, meaning it will suck in the paint like a sponge at first.
Just let the first coat of primer fully dry before applying the second coat of primer and you should be sweet.

One other thing you could use is wood putty that you would use in woodworking to fill nail holes and cracks.
It's normaly an oil base filler that drys hard and can easily be sanded back and then painter over.

Just see what you can find, you will find something champ.