The closest players I can find to Jack Slugger's and Mickey Slapper's statistical profiles might be interesting:
Gorman Thomas and Rob Deer are pretty darn good comps for Jack Slugger, although Slugger is better than both of them. They both played in an era when offense was down and fewer runs were scored.Code:Player PA AB Singles Doubles Triples Homers Hits Walks HBP TB TB+* BA OBP SLG OPS wOBA Jack Slugger 600 503 42 25 2 32 101 95 2 226 323 0.201 0.330 0.449 0.779 0.343 Gorman Thomas 619 528 64 24 1 30 119 79 2 235 316 0.225 0.323 0.445 0.768 0.335 Rob Deer 633 544 65 21 2 32 120 81 4 241 326 0.221 0.324 0.443 0.767 0.336 Mickey Slapper 600 574 112 44 6 10 172 24 2 258 284 0.300 0.330 0.449 0.779 0.339 Nick Markakis 703 626 124 41 2 18 185 67 4 284 355 0.296 0.364 0.454 0.818 0.358
Nick Markakis is quite a bit better than Mickey Slapper (his OBP is 34 points higher) so he is not really a good comp, but I can't find anyone that closely fits Slapper's odd slash line. It seemed like most of the closest matches were from the 1930's and earlier.
I used the comps' 162 game career averages.