starting 1970 c10

All depends on if you dont mind busting the top off the steering colum, located under the top side of the steering colum under the top cover of that is a rod that runs down into the dash. The rod can be used to actuate the actual switch that is located under the dash and is mechanicaly connected to the key slug. Dont remove the rod just expose it so u can push it inwards to run the vehicle. When finished Just wrap a bandana around the colum and no one will know. Option two is, do you live near a large city or by chance is one of your nieghbors an old school coke head from the city. If so, they should know how to use a slide hammer to pop the key slug out and then you can use a screwdriver to operate the hiden rod that i just mentiond. If it wasnt dark outside i could send you a picture of my 78 cj 5 that is started by pushing in on the rod. I also had a 92 s- 10 that i drove for a decade like that. Idk if i can post a contact info or not but if you respond i could try to assist you.

would it be possible to just buy a new ignition switch? and replace the old one?

Yes you will need a steering wheel puller. They normally can be borrowed from places like autozone

Yes that's the best way. But you need it started now. Take a wire with alagator clips. Run from the hot on your batt to your distributor. Make sure your not on the tach side. Sure you don't have a hand held button to hook up. But jump starter post to post. To turn it off you will have to unhook wire from battery. If you do that and don't get fire Ignition ain't your only problem

Will that rod need to be cut free from the ignition switch ?