Hey folks.
I'm relatively new on these forums. First off, I apologize if I'm posting in the wrong place; any help would be great.
The thing is, I have a set of 1967 Malaysian coins, non-proof I think, (issue of 12th June, 1967) which I received from a friend. Now, it probably wasn't worth much to anyone else, but I recently had an offer from someone (in Malaysia itself) to let go of the entire set for 912 Malaysian Ringgit (around US$276).
Attached is the set of coins:

I have a few questions:
- How can I tell if they're proof coins?
- What is the perceived value of this full set of coins?
- What else should I look out for if I decided to let go of it?
Any help would be greatly appreciated. Thank you. :)
Edit:
If someone could direct this thread to the appropriate section, that would be great. Sorry about that.