Here are three from Tower (just do a search for test stand):

1) [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXA378&P=ML]CBA/Tatone Engine Test Stand w/Tank[/link]
2) [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXA379&P=ML]CBA/Tatone Giant Engine Test Stand[/link]
3) [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXR587&P=ML]J'Tec Test Stand Giant 1/2A-2.5[/link]

Here is one from PSP: [link=http://www.pspmfg.com/EngineTestStand.html]Engine Test Stand[/link]