What is this one?

[Chainshot]

I know everything has been replaced on it. Frame and handlebars are
probably the only original items?

Thanks.

 

[Stangrcr1]

Trail Blazer, same as a Trailhorse except the forks.

Trailhorse forks come straight up, where the Trail Blazer forks are bent out over the trees.

 

[SimpleTom]

Trail Blazer LTD 230 or 330 depending on what engine it had originally. Looks like the wheels and front fender are original.

Top bike on this brochure.

The LTD 130, which had 4 inch wheels, came with a seat like yours but that is most likely an aftermarket replacement that you could buy from Northern Tools or other stores that sell mini bike parts.