SBP Disc conversion keeping the Drum spindles?

Wilwood makes that kit, it's available in both 9" and 10" drum configurations. You'll need a 16" wheel, I believe. Still, worth the ~$100-200 more than a stock-type Disc brake kit!

10":
WILWOOD 140-11023-DR MOPAR A BODY FRONT DRILLED & SLOTTED KIT - RED #6198 | eBay

Just Ebay search "Wilwood mopar a body" and you'll fid it with a few clicks!