Who are these specific congressman or senators you've screened?
I started a spreadsheet today, lol... just to get a sense of how narrowly I can define my key issues without ruling out over 90% of congress. I've only looked at senators so far, because the house is 9x the work.
Manchin (D-WV) seems the closest to my model senator. He has a reputation as a "conservative Democrat", has some of the highest fiscal scores for Democrats among conservative institutions who publish such ratings (i.e. Americans for Prosperity), voted yea on
this bill, and cosponsored
this one, which is the only post-recession balanced budget bill I've seen with a bipartisan group of cosponsors.
McCaskill (D-MO), Tester (D-MT), Carper (D-DE) and Bennet (D-CO) also voted yea on the above bill and have decent fiscal scores from Americans for Prosperity or similar groups.
Heitkamp (D-ND) has a reputation as a moderate, high fiscal scores from conservative groups, made balancing the budget a campaign issue when she first ran for senate, and has cosponsored a dem-only balanced budget bill, but she hasn't voted yea on any of the bills I've seen that went to vote.
As for
the bill Rand Paul introduced this year with deficit reduction measures, there are two Republicans who voted yea and are relatively close to the economic center in a National Journal ranking: Daines (R-MT) and Lankford (R-OK). Shelby (R-AL) has a similar National Journal ranking, and voted nay on a successful
2015 bill which allegedly ended the pay-as-you-go standard.
McCain of course has a reputation as a moderate. I haven't seen meaningful support from him on balanced budget proposals, but he was the only Republican not to vote for the 2017 tax cut (he abstained).
"Rigid Tea Party" candidates are the only place you're going to find fiscal conservatism in the Republican party. Who are these specific congressman or senators you've screened? Two of the three guys that authored the bills you posted are Tea Party people. The other one is apparently retiring.
There's nothing conspiracy-theory about it. Politicians are put into power largely on the basis of what they promise, and to whom. What they promise is a juggling act between moderates and extremists, and in practice the overwhelming majority, at least on the federal level, do not deliver on promises of change. At most they engage in gridlock and refuse to budge; this is why evangelicals are still happy to vote Republican, even though Republicans have failed for almost 50 years to ban abortion (though on a local level there is some evangelical success). This is also why it's more productive to vote for an opposed congress and executive; Reps will refuse to endorse big pushes on medical/welfare spending, Dems will refuse to endorse big pushes on military spending.
Good point about opposed congress and president, but I'm not convinced that the Tea Party senators are a bastion of GOP fiscal discipline, since they all voted in favor of the 2017 tax cut.