https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
I replaced both of those exact same plastic drain valves less than two months ago due to a slow dripping leak they developed over time. I used shark bite style replacements from the link above. You can ignore the ends you see in the picture that have the 3/8 " hex nuts on them. You can throw those nuts away as that will be the bottom drain end with nothing else to connect.
The main thing with the sharkbite types is that you need to cut the old ones off with a clean 90 degree square cut for the new ones to seat and seal properly. Looks like you have plenty of spare length to cut just above the old metal clamps. You might be able to use a PVC tubing cutter, if there is room to rotate it around 360 degrees for a clean cut. I had to resort to using a pair of large tree limb lopping sheers to finally get a clean 90 degree cut. The new valves slid right on after that with no more leaks at all.