Trump can clinch, I think, on the first if he's within 50 or so. Starts next week - run up the score in the northeast!
Who on earth not forced to vote for Trump would do so voluntarily? I doubt he will get many more votes. He'd be lucky to get 10 more. But maybe you or somebody has more information on that. Just who are these susceptible creatures to the Trump siren song?
Many Pennsylvania delegates say they will vote for the winner of their Congressional district, so a large win in PA could easily net Trump half of those delegates (if they keep their word).
The uncommitted insular delegations (American Samoa, Guam, and the Virgin Islands) have 27 delegates, of which 3 have endorsed Trump and 2 Cruz. They could very well be receptive to Trump, though Guam is difficult territory for Trump and the Yobs (assuming they are seated) almost certainly will not vote for Trump on the first ballot. That leaves only 10 truly in play, but they could make the difference if Trump is inches away.
Beyond that, if Trump is only a handful of delegates away, one can imagine that 3 or 4 out of the 186-odd unbound delegates could be convinced in the name of "party unity" or some such; the remaining PA unbound delegates are the most likely target.
Trump can still win on the first ballot if he does very well in the Northeast and does any of the following three things:
A) Wins Indiana and does not lose California
B) Wins Montana and does not lose California
C) Wins California by a large margin (115+ delegates); if he does well in the heavily-Democratic districts in LA, this may be possible.
If he only does okay in the Northeast (sweep but not a delegate sweep), it gets tougher.
Your numbers assume how many delegates in the NE (outside of PA), in contests yet to come, are not Trump delegates on the first ballot? Zero? Because I think that maybe 10 or so delegates out of New York are more likely than not to be Kasich/Cruz delegates. And then there might be another 6 out of Maryland (Kasich should carry the Montgomery County CD, and the one between it and Baltimore at least (MD-03 and MD-08 - God the map is a most butt ugly gerrymander!).
