Okay that's a nice one. The SP version of that one is probably going to be like a model 8237, made from 1978 to 1983. Those are really good F series cast aluminum deck mowers, very popular indeed. If it's in good running condition and was very well cared for I would think it could very easily be worth 150. The usual things to look for would be cracks or holes in the deck, bent crankshaft, and excess side and end play of the crankshaft (kinda common on a high time engine) fuel leaks around the tank/shroud. Good luck on that one, I have 3 F series mowers and I really like them a lot. By far the strongest running true Lawnboy (OMC) engine. The later engines like the V and the E series were really Toro products.
