Hi Fairydream,
Price is definitely more expensive than in the US, even after calculating shipping, unless the various vendors have lowered their prices.
If you're going to spend on a CG-5, may I also suggest used mounts - there are some for sale on this forum although mostly for lighter scopes - depending on the weight of your imaging setup

I'm sure the owners will run you through completely before closing the offer.
Unfortunately I'm not sure if mount AND telescope for less than USD1200 is doable if both new.
Astrobargains quotes the CG-5 at SGD$1749 and if I remember correctly, Astro-Scientific quoted me in excess of SGD$2000 a few months back.
In contrast,
www.optcorp.com quotes the CG-5GT at USD595; I'm not sure how much it is to ship to Vietnam but it will cost in the hundreds of USD to ship here.
I ended up buying a used Vixen SXW
