selling my ipod touche original 1st generation 16gb in flawless condition

There's no definitive answer to your question as someone will only buy it if they think it's worth your asking price. That's something only a prospective buyer can decide.

Bear in mind though, that even if you think it's flawless, the battery is old and the time between charges will be much shorter than it was when new, plus the battery may not take any charge at all for much longer. In addition, apart from the built-in apps, there will not be any other apps that can used on it as the apps require a later version of software that the 1st gen Touch cannot install.