Interesting Old Stamp Packets

I found these interesting, this is the way apparently some collectors used to buy their stamps. Send in ten cents and they would send an envelope with 20 Rulers or 25 Air Mail & Transportation stamps. You never knew what you would get. Hey its only ten cents right, of course ten cents back then is not ten cents today. I have several different companies stuff. Toebeck Buying Syndicate, Stamp and Album Company of America, and Hygrade. I am thinking the packets could be collectible in themselves so I have been careful with them some are sealed from moisture in the air. The stamps inside are in great shape. Whoever originally bought them never took them out. I don't have a international catalog I need one bad for these. I can't even tell what some of these countries are.