Visa Medical? (Johannesburg)

Hi all,

I'm in the process of applying for a work permit in Johannesburg (I'm already here as a a temporary resident without permission to work) but my medical check from the UK expires in a few days.

Can anyone advise

a) If they are strict on the rule that the medical must have been completed in the last 6 months

b) Where I can get a medical done in Johannesburg (bloods, physical, xray) that is sufficient for visa requirements? How much should I expect to pay?

Thankyou so much in advance!