In general that's not really possible. If you had a corrupted bootstrap file (a different chain-state from the actual one) it would fail. Best thing would be to ask a friend to bootstrap their sycned wallet. I think Bitcoin.org used to maintain one as well but afaik they stopped. At one point there was an update for better syncing and everyone stopped doing bootstrap files. Fun fact, a recent bootstrap is still much faster than a sync from scratch.