When I played Tie Fighter, I remember seeing a TOPACE10 savegame with the game completed to almost 100%.

Is there a way to obtain a similarly complete savegame/pilot that I can import into X-Wing vs Tie Fighter? Thanks!

No, X-wing vs Tie fighter allowed to play every mission from the get-go in its base version so it wasn't necessary.
Only the expansion had a campaign that you had to play in order to unlock the various missions.
There is also the fact that you are locked out of the top ranks and half the campaing medals unless you play multiplayer, I did complete the game about a year ago (at the time I couldn't beat some missions because real life got in the way) and still have the save file if you wish though it's still technically not 100% completion (I don't play multiplayer and I still have to try a few of the "meelee" missions) all campaign missions are unlocked.

Thanks @Det_Bullock for the informative reply. I'm actually a bit disappointed that some of the achievements require multiplayer, since I doubt I'll be able to find any servers/people to connect to these days, not that I am any good in multiplayer anyway.

But sure, if you don't mind sharing your save file anyway, that,'ll be great!