Patrice,
You certainly can make one or two carving blades yourself. Besides being the simplest of shapes ( Wharncliff), they are usually just an ugly old bench knife, so no fancy work is required. The main thing is that they need to be thin and tapered, with a straight edge. About 1.5-2mm (.060-.080") tapering to .1-1.5mm (020-.030") is the right thickness for a carver. A 25-35mm (1" to 1.5") long blade is usual - my most used carver is 25mm. The tang should be 2-3mm (.080-.100") thick, for strength, and carry this thickness into the ricasso. It needs to be tough,so make sure you pick the steel well. mete's A-2 offer is one good choice, and 1095 is superb. HT is everything in a carving blade.
If you just want to do the handle work, Jantz ( and others) sells the standard four blade set for $20, which has chip carving blades in it as well as standard blades.
http://jantzsupply.com/cartease/item-detail.cfm?ID=SS263
I used to test some products for Woodcarvers Supply. They sell top quality carving supplies and knives.
http://www.woodcarverssupply.com/store/
430000 is a standard carver shape, and 577016 is a nice handmade carver they carry.
If all this is more than you want to go through ,just to whittle on a stick at camp, I have many spare carvers sitting on the woodcarving bench.When I used to teach the scouts to carve ,I had them in several handle and blade sized. I use my favorite one 99% of the time, and the rest sit in a tray. I would be glad to send you one. It will be like the 430000 one I mentioned from Woodcarvers Supply.
Stacy