Ice,
That spider from down south is right, on getting the UHC from the US. I have brought plenty from the US and have never had a problem.
If you don't feel comfortable with buying from the US then go to Bintel. May cost a bit more but you soon forget that.
As for color filters, this is really what suits you. I'm a bit color blind. I find the red filters don't do much for me.
I mostly use the blue and green ones. I paid around $35 for each filter. This was to much and considering I don't use them much, you are better of going for the ones at Andrews.
Try to get a look through a few filters before you buy, if you can.
Mars will be back later next year, so if It was me I would get the light blue and light red ones first.
I think Andrews sell a set of 4 or 6(anyone?) There cheap and would be a good investment.
I checked back through some of my old notes and i found I use my LPR filter more than any other!! But I would still go UHC first.
Best.