For simplicity, I would try v2 at $5 first:
Elite Workshop v4 (Action) $5
Gain a card costing up to $5 and put it on your queue pile.
Some non-Actions:
Clerical Seal (Treasure) $5
Worth $2
+1 Buy
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While this is in play, when you gain a card, put it on your queue pile.
River Island (Victory-Reaction) $3
Worth 2 VP
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When you discard this other than from your queue pile, you may reveal it. If you do, put it on your queue pile.
Ruby (Treasure-Reaction) $4
When you play this, count the cards in your queue pile.
Worth $1 per card in your queue pile.
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When you gain a card, you may reveal this from your hand. Put the new card on your queue pile.