A LL Pioneer is around $2400 new, not $3500, and that's with a coal-trol.
I like Yanche's point of view,, try it for a year,, save a significant amount of money over burning oil,, and keep looking for a boiler.. A good used boiler is usually around $2000 or so. BIG savings over a new $5200 one..
My AA 260 was $1500 used,, New it's about $8000, I have a lot of work and some new parts involved in rebuilding it,, but I know the boiler inside and out. Important for me, since nobody is going to fix it but me anyway.
There is no question that a boiler is the way to go,, eventually..