If your father wanted to use pens he would need to use insulin that comes in disposable pen or cartridge form.(the cartridges are prefilled, you put them into a non disposable pen. You don't buy a pen and fill it with insulin.
I don't know what part of Asia your father came from but I did some research on insulin availability in India.
As you probably realise, there are very many different types of insulins (they vary in what they are made from, how long they last and some are mixtures of 2 different insulins. They can also vary in strength, though in Europe and the US it is almost always a strength of U100 )
The big insulin companies Eli Lilly, Aventis, Novo Nordisk all market insulins in Asia. Wockhardt, has also got a large market and makes insulin in Asia. The modern insulins they produce are available both in vials for syringes or in disposable pen or cartridge form. All these 'branded' insulins are many times more expensive in pen form than in vial form.
The Wockhardt pen mentioned by Sue is one of these, it's cartridges contain a specific type of insulin (wosulin)
http://www.wockhardtdiabetic.com/inner/pen_royale.htm
If your father is using one of these insulins then he could obtain them in cartridge form rather than a vial and buy the appropriate pen. Wosulin seems to be cheaper than the other brands and comes in several different types including a mixed insulin .
However, according to Diabetes India the majority of insulin used in India (and I assume this may be the case in other Asian countries) is not modern branded insulin, it is generic insulin and in India most of it comes in U-40 strength. These insulins are cheaper than the branded insulins but they do not come in pen or cartridge form, only vials. If your father is on one of these generic insulins he would have to ask his doctor to prescribe a suitable alternative that was available in pen form.(at a considerably higher cost)
Modern syringes, If your father has the dexterity to use them are a good option. In Europe most people use pens but there are many in the US who say that they prefer to use syringes. Indeed I think there are a couple of people on this forum who also prefer them. The BD India site shows that syringes are available for both U-100 and U-40 insulin with very fine needles. It also has an 'injector' which hides the needle . (similar to that mentioned by Sue above, though such a device still needs someone to fill the syringe and put it into the injector)
http://www.bd.com/india/products.asp under Diabetes Care.