JimmyAstro,
Welcome to the hobby, can I first ask you a question. You mentioned astrophotography, what do you want to take images of and how good do you want your images to be. This very simple question not answered can send you on a quest which will cost you a lot of money when not required.
Direct responses
1. Budget - the word astrophotography means you will have to spend some money, do you have a budget in mind.
2. There are many light weight rigs out there you do not have to go big. It sounds like with health issues big will never be something you are looking at.
3. This is covered by 2.
So having said that you will require the following.
1. A nice mount, you really need to look at a go-to mount. A manual mount when you travel to sites will not be fun, a manual mount for astrophotography is a pain. If you go for a manual mount from the start when planning out imaging then you will soon pack things in the corner and say its all too hard.
2. A nice small refractor will get you lovely images for a beginner.
3. A camera, a lot of people start out with a cheap DSLR, these can be picked up on marketplace for a $120. The best thing about these is you can use these without a laptop when starting out.
4. A focusing mask
5. A computer, but this does not have to be a travel one. You do your work on the computer when you get home and transfer your images from your camera.
6. Software to stack and process your hard night of imaging. There is enough free stuff to start out with you do not have to spend a penny here
This is now where your budget can take a hit. You go a big mount, fancy camera, a laptop, then you need power etc, lots to carry etc etc. This impacts all 3 of your criteria. Below are just examples, I am not saying go out and buy them in anyway there are other options out there
Mount - Star Adventurer GTi with WiFi Control - This unit can be controlled by your phone is fully go-to and runs with AA batteries
Scope- Evostar ED 62 or ED72 Refractor - small and very nice to use and give great results for learners
Camera - Canon 450d-700d. (Do not purchase a 750d)
My site rig is the above mount, ED62 and and a 450d. This whole unit is light and easy to setup.
Having said this, use Dr google and look into a few things, work out how much you want to spend first. You can get a lot of good second hand gear on this site for great prices and you will not go wrong with the people here as they will always help.
IMPORTANT: Do not rush into anything.