Those are some pretty old limbs by todays standards.
The only thing you can do with them is shoot them on the riser they were designed for.
No,you can't make them ILF.
The MIND 10 through to 50 was a good enough shooter for a cheap bow but never anything to look at.
I'd put it togeather an hang it on a wall.
The 66" and 68" marking on the limbs indercate a 66 and 68 inch bow.
To order or buy a string,tell them those bow lengths and any shop or supplier will know what you need.