with all the attachments that are for it due you have use of all of them and what type of shape are they in?
ball park would be $200-350
that is if the sickle/chipper/tiller all look to be in good shape and not been stored outside the last 15 years
max I would pay would be $500 and most of that is for the attachments that you can put to use once you get the tractor running and working.
that is also if you have work that those attachments can due.
plus look's like there's a CB radio on the side the tractor?
good luck. also due you have the time and mechanical ability to get the tractor running?