Replying to [peter king]:If you only want to buy "A" computer, then why not go to the store that sell computer and get one. The price maybe a litte higher, but you will get what you want and not junk.
He may be directed the "a" part as though he's sample order is of one unit only. But he may now know, if the sample's quality is to he's desire. No reason to make asumption's without enough speech from he's side.
Replying to [peter king]: For some items samples are not easily available. For low value items you can expect the supplier to send samples.
But for items like computer, you have to look at the designated places like department store. If you want a computer manufactured in your country surely it will be in store in your city or in a big city next to yours.
I doubt you want to import a single computer from abroad.