http://www.pcandparts.com/price.htm usually have the best prices in Lebanon, and a huge variety of hardware, it will take them some time (like a couple of months) to get the new GeForce cards and they will be expensive another couple of months or even more, check the prices for the GTX 780 and 770 right now at PCandParts, you will notice Amazon + Borderlinx are your best option.
To answer your question, yes of course a GPU will cost less than a laptop, less weight, less price, les VAT etc ...