­Trinket Mage + Seed: 1464276965
(Which is: Creature - Human Cleric (3/1, white)
All Clerics can block an additional creature
Whenever one or more creatures becomes blocked by one or more creatures, you may pay (W/U)(W/U)(W/U). If you do, search your library for a Forest card and put it into the battlefield, then shuffle your library
Converted mana cost: 1 )

Ok, nifty "Clerics can block" plus land search plus artifact search. Well, replacing the land with.. white.. equipment search is probably nice.

Sadly, that probably makes the card splashy enough that the double-block thing is wasted. So leave it off.

It's more normal to search for equipment based on their CMC, not their converted equip cost - which as you say can be weird things like Piston Sledge. White gets to search up equipment in any old way (Steelshaper's Gift, Stonehewer Giant), so either is fine in white's pie. Should this be 2/2?

BTW, be aware there was a stupid broken card called Stoneforge Mystic that played in this space and was eventually banned. That was broken because it got whatever equipment you wanted for just 2 mana and then bypassed mana costs; so this is safe because it's harder to get your stuff blocked and this doesn't bypass... um... actually, what is this meant to do with the searched-for card? Put it into your hand, or onto the battlefield? At the moment you find it and then shuffle it away.....)