The wiki has a good list of the normal equipment you'd want to use. https://irowiki.org/wiki/Arch_Bishop
The quick version for good cheap items would be (in order of importance);
Light of Cure with the Cure1 enchant (spam High Heal): 50m
+7 Recovery Light (higher heal % for more sp): 150m
OR if you run out of SP all the time +7 Healing Staff: 7m
+6/+8 Chibi Pope with Parus Card and Blush mid headgear: 80/200m and Blush for 2m
OR if you want something other than blush in mid then this: +7/9 Yggdrasil Crown (7%/13% heal bonus): 100/150m
Diabolus Robe (6% heal bonus, 10% less cast delay): 75m
Valkyrja's Shield with Hodremlin Card: 80m
+7 Heroic Backpack with Raydric Card: 650m - expensive but worth it as it has a strong buff for every kind of character also greed is fantastic
Valkyrie Drop (sp recovery and Power of Odin skill): 175m
Variant Shoes (20% hp/sp) 1m
Anyway that'd be a great start and will be almost at 1.4b
Hope this helps!