I am buying a new computer and I do not want Photoshop Elements 15 because the functionality does not meet my needs. However, I use PSE version 8 which fits all the needs I have; this was purchased bundled with my old computer so I am unable to port it to the new machine. My question is...can I purchase Photoshop Elements version 8 (I am aware that this is probably no longer supported by Adobe)
Simple answer is no. Adobe stops selling old versions as soon as new versions are released.
You can try the secondhand market but beware that pirated copies are everywhere and you're never sure if you've bought a pirated copy until you try to register the serial number.