According to the SCD, 1979 contained more than 50 TCMA team sets, covering teams from Florida to British Columbia and Massachusetts to California. (This is the blog's 5th profile of a TCMA minor league set and first from that prolific year.)
Future big-leaguer Brennan had no problem holding the pose you see, left leg cocked and held at the ready. In fact, he usually pitched with a significant pause at the leg-lift stage, similar to Hideo Nomo's full-stretch windup. (Check it out in Nomo vs. Ichiro, circa 1996.) Tom eventually released the ball sidearm, a complete delivery that no doubt puzzled opposing batters.
Tom spent a long time in baseball, with 12 seasons of minor league work sandwiched around a full year with the Indians in 1982 (full stats at Baseball-Reference.com). He played for 10 different Cleveland farm teams from 1974 to 1983, including two quality years with the Tacoma Tugs in 1979 and 1980, where he went 21-10 with 4 shut-outs.
Value: My 2010 SCD lists the Tacoma Tugs set at $17.50 and I picked up this #5 for $1, about what you'd expect to pay for that era.
Fakes / Reprints: It's likely people have reprinted valuable minor league league cards of major stars, but I doubt it'd happen for lesser-known players.