birdo's idea isn't a bad one, but I'm not too big on the tandem set up due to flexibility issues. That being said, and to give yourself some breathing room, I'd consider:
'50 Hearn, 141 IP, 6.09 IP/G, 237 ERC+, .182 AVG#, 149 HR+
1943 Pollet, 125 IP, 7.40 IP/G 200 ERC+, .203 AVG#, 229 HR+
'90 Tudor, 147 IP, 5.85 IP/G, 162 ERC+, .228 AVG#, 128 HR+
Of these three, I might lean towards Pollet as he's a y. Balances out
your other two guys a bit. All these guys can be set to relieve a bit as necessary.
If you want to go cheaper than this, the 104 IP Woody Williams is only $2.9Mm and can go 6.06 IP/G and has a 156ERC+.