Buy Mitutoyo or Brown and Sharpe micrometers used off of someplace like ebay. You can also check your local pawn shops and craigslist. For the very limited use you will have for them do not spend too much. Many of my Micrometers are used Mitutoyo pieces from the 60's and 70's that I picked up from machinist getting out of the trade. Most machinist like myself take extremely good care of our micrometers and despite their age mine still pass bi-annual calibration with flying colors. I paid between $15 to $45 for used Mitutoyo micrometers in 0-1" to 5-6" sizes.
Calipers are a different story. They are not nearly as accurate, durable, or reliable as some folks think them to be. Any good machinist will not use them to check anything with a tolerance tighter than ± 0.005. They get used for quick checks of looser tolerance items and non critical work. They also are frequently out on the shop floor getting bumped around on tables and covered in coolant. For this reason I do not recommend buying used calipers. There is also no need for a home shop user to pay the extra for a quality digital set of calipers. Buy a good solid set of dial calipers. I recommend Brown and Sharpe, Mitutoyo, Mahr, and higher end SPI. Avoid cheaper SPI, Fowler, and cheap Chinese imports. You should be able to get a nice pair that will last you many years if cared for at prices under $100.
Those telescoping gauges take a bit of time to get used to. You have to develop a feel for them but once you do they are very useful. They can be had inexpensively but avoid the cheapest Chinese imports. They often have a sticky action and the thumb locks do not hold well. I think SPI makes some less expensive but solid sets. If you can buy a cheap ring standard of known bore diameter, you can use it to practice and develop the feel. A ring standard that is no longer certified should be very cheap. I may even have one I can send you from my lab.
If you wish to shop non used items check out MSC, Enco, and Travers. They have good online catalogs and carry most everything you would want o0r need. I can actually send you some 15% off coupons for Enco if you see something you like there. I picked up a couple at a tool and manufacturing show recently.
