I can't say from here whether it's worth $100.
I like people to come to our forum here but also recognize we're not the best in all tractors, especially some smaller vintage tractors like yours.
I'd like to suggest you go to yesterdaystractors.com and look around there as they're more in line with what you may need in terms of knowledge, values, parts and maintenance.
I just did a quick look there. Using their toolbars on the left, I found tractor values & your Sears is in there. Don't know condition or anything for asking price.
They may also be a good source for selling/trading what you don't need (e.g. the hood and fenders) and getting what you may need.