Wait, this is for a 1st edition Advanced Dungeons & Dragons game, correct? Does that edition have ki straps? What do they do?

If you are playing 1st edition AD&D, your best bet is to use Oriental Adventures and take the martial arts proficiencies (I believe the system actually modifies and or replaces the monk-class unarmed damage stuff, but nothing else; this let's you use the best martial art while maintaining stunning fist and such), so you can do neat stuff like auto-grapple an disarm in a system that isn't designed for them, sunder weapons and armor, break objects, deal extra damage, etc. which can come in really handy. Some of them were pretty automatic as far as choice, I think there's one that completely removes terrain restrictions, letting you do those flying Jumps from Crouching Tiger, Hidden Dragon.

That's... Really all I've got.if you're doing a monk, you get the most out of picking a culture and working with that. Without ideas as to what culture, can't really make any suggestions.