RS,
1) - Is there such a thing as high temp silicon I can use to MAKE a door gasket?
As mentioned by MH8675309, there is a specific material for stove door gaskets: fiberglass rope
I just did the main door on my Vogelzang double barrel stove up in the shop a few days ago. Used a kit by Rutland that I picked up ten or so years ago - looks like this (image courtesy of walmart.com):
Ideally, there should be a channel on the inside of the stove door for the gasket ... but there may not be, given that it was home-built. Regardless, you can cement the gasket in place where it needs to be, channel or no channel.
Key thing to know about cementing it: The stove cement in the kit above is water-soluble (it contains water) ... they tell you to knead the tube before opening (because the water in the cement separates) ... it's good very advice - be thorough.
Mine was so old and separated that I had to cut the top off the tube and dig it out and then add water and work it in a dish with a piece of 5/8" steel rod (mortar & pestal) to get it thin and gooey enough. Should be about the consistency of "thin" putty or caulking (but not "runny") ... because you want it to embed into the fiberglass rope.
Measure out the rope gasket material before you start with the cement. Better to have the rope a little too long than too short. If you need to shorten it, trim it when you actually place/cement it.
If you don't have a channel in the door to place the cement into, I'd pull the door off and lay it flat (a good idea in any event) and place a bead of the cement where you want the gasket to be and then place the rope gasket onto the bead of cement, and work the cement into the gasket a little ... but not to the point where the cement is coming thru the rope gasket to the side of the gasket that will contact the stove.
The metal where the cement will be placed needs to clean - preferably bare meal ... wire wheel in an angle grinder.
Give the cement 5 or 10 minutes to set up a little (so the gasket doesn't slide out of place) and then CAREFULLY take the door to the stove and put it back on, then close the door and clamp it shut. Leave it dry for awhile (6 hours ?) and then fire it with a small, low heat fire or two to cure it.
2) - After I am working and have paid off all the lawyers, fixed the leaking roof, etc, I will def look into the 2 45's and maybe put a damper in even ...
Yup ... damper is a good idea. The 45's are relatively cheap ... reuse the straight pipe that's there if it's solid and not rusted out.
3) - the electric dryer vents into the basement where it sits, yes there is a Heat Pump fan on the main floor.
Doesn't seem like any of those would be a problem
I was looking for an appliance that needs air for
combustion - which could create a negative draft down your stove chimney.