Why do you want to replace them?
If they are noisy you mya want to try what solved the problem on my 98 V70.
After doing an oil change, make sure the oil level is right at the mark, add a can of lifter conditioner (or something similar), add 1/2 qt. more of oil and run it for about a month, keep the oil level above the full mark (by 1/2 qt.) all the time.
There is a chance that the O rings in your oil pan are cracked and sucking air.
It seems that by keeping the oil level a little high the oil pump does not suck air that gets lodged in the lifters.

To all the ones that are going to tell be how bad it is to overfill the cranckcase, please save your typing.
I have been doing this for over 2 yrs. and not one hing of lifter noise.

is the issue that your lifters are sticking? Try running a can of sea foam or marvel mystery oil prior to an oil change to clean up any sludge. Another way is to use Mobil1 oil, which contains high detergents and will clean sludge out. Beware though, if you have lots of sludge and start using synth, you should expect to do some frequent oil changes as the oil will darken need replacing faster than normal.