Don't wear chaps to climb...too many buckles and bits to get caught on stuff.
I used to have SIP Traditions...or at least their earlier model trousers. Since then they and many others have come out with superior models that are lighter and thinner.
If you are looking for some trousers that are a good compromise, not too expensive, yet use the more modern materials, 'Francitals' from TreeStuff are pretty good if I do say so.
Yes, they are black but the fabric wicks and is breathable. They fit well and are stretchy. I've worn them from frosty days in Tasmania right through mid summer in hot humid Bermuda.
$199 was the last price I saw (last year...)
If you just want a pair of buckle on chaps for ground work, just about any of them are fine, just make sure you get the ones that wrap around your lower leg completely.
Also, being in Australia, check out Clogger brand...AUS/NZ certified. Made in NZ I think.