Just won the WS with a rotation of 1914 Russ Ford, 2010 Trevor Cahill, 1904 Barney Wolfe, 1906 Beany Jacobson, and 1981 Vern Ruhle.
Wolfe costs $3.6M for 173 RL innings. Jacobson costs $3.5M for 165 RL innings. Ruhle costs $3.5M for 151 RL innings.
In the regular season, Wolfe went 17-5, 3.43, 1.38 WHIP. Jacobson went 15-4, 2.92, 1.23 WHIP. Ruhle did not fare quite as well: 9-13, 5.42, 1.40 WHIP, though that's least partially tainted by 2 games where I left him in to throw a zillion pitches and he got killed.
For those who think deadballers like Wolfe and Jacobson will get hammered by unearned runs, I will point out that they gave up 4 and 5 unearned runs, respectively, all season.
In the postseason I went with Ford-Cahill-Jacobson, and ol' Beany was even better: 2-0, 0.64 ERA, 3 total runs allowed in 28 1/3 innings.
There are good value SP under $4M out there, but more importantly, you can absolutely win in SLB without trotting out the same cookie pitchers time and again.