[Orca, Orca - Tank]

Damage Control II
Reinforced Bulkheads II

Large Shield Extender II
Adaptive Invulnerability Field II
Adaptive Invulnerability Field II
Pith A-Type X-Large Shield Booster

Medium Energy Neutralizer I
Medium Energy Neutralizer I
Prototype Cloaking Device I

Large Transverse Bulkhead II
Large Transverse Bulkhead II
Large Transverse Bulkhead II


Zainou 'Gnome' Shield Management SM-703
Inherent Implants 'Noble' Mechanic MC-802
Zainou 'Gnome' Shield Operation SP-903

Combining two different fit ideas that I'd seen; one where you add one or two Large Shield Extenders, and another where you use an A-Type X-L Shield booster (these only cost about 100m in Jita, or slightly more than the three bulkheads). Gets around 420k EHP before overheats against a Tornado (430 after overheating), 430k before overheats against a Catalyst (436 after overheats), and repairs around 800 EHP per second before overheating (around 1000 after overheats). Cap lasts 50 seconds with just the tank mods, 36 seconds with the neuts (it's something to potentially fight back with in a gank, rather than sitting around with two empty high slots).

Total cost is only 900 million ISK, including hull (around 920m with implants)

EDIT: With some suggestions below, I've come up with this slighly more expensive fit:

[Orca, Orca - Transport]

Damage Control II
Reinforced Bulkheads II

Pith A-Type Thermic Dissipation Field
Pith A-Type EM Ward Field
Adaptive Invulnerability Field II
X-Large Ancillary Shield Booster, Navy Cap Booster 400

Medium Unstable Power Fluctuator I
Medium Unstable Power Fluctuator I
Improved Cloaking Device II

Large Transverse Bulkhead II
Large Transverse Bulkhead II
Large Transverse Bulkhead II


Zainou 'Gnome' Shield Management SM-703
Inherent Implants 'Noble' Mechanic MC-802
Zainou 'Gnome' Shield Operation SP-903

Comes out to 950M ISK with implants and hull. Has 427K EHP against a Catalyst and 445K EHP against a Thrasher, with 1.4K regenerated per second with the shield booster.