We're going to need to need to source or develop a 1,000 lb. APHE bomb.
We need to define what a APHE bomb is.
Armor
Piercing
High
Explosive
Was term often used in artillery or tank gun ammunition.
Less so in naval guns, they had different terminology even if perhaps the intent was the same.
For bombs the criteria was way, way different.
Converting naval shells to bombs was a somewhat cheap way to get a small number of bombs in a hurry.
I say somewhat cheap because it took an awful lot of machining on the body of the shell to make even a 1/2 way satisfactory bomb. It was faster than designing and building a new bomb casing of forged steel however. Or depended upon the ability (or inability) to provide quality forgings of the appropriate size. The Japanese AP bombs converted from 16 in naval shells were almost 500lbs lighter than the parent shell. The interior of the shell was bored out and accommodated around twice the explosive.
The British 500lb SAP (Semi Armor Piercing) held 18% explosive by weight.
Naval AP shells were most often between 2 and 4 % HE content. Some navies may have used the term APHE, others used the term "common" shell and some used SAP. HE content was from about 4% to a bit over 6%. These were base fused. Naval HE shells often were nose fused and the HE content was usually between 6% and 10%.
The British used a lot of crappy bombs in the early part of the war. Not only were there no 1000lb bombs but the standard British HE bomb design, the G.P. Series was about 29-31% explosive by weight. The US GP bombs and the German SC series were around 50% explosive by weight. The British got to this level with the M.C. series of bombs. (Medium Case). But the 1000lb MC bomb didn't go into production until the spring of 1943.
The British seemed to be obsessed with using the cheapest steel they could for bomb bodies and artillery shells. Cheap may be good but not if you have to fire (or drop) a lot more shells/bombs to get the same target effect.
Back to the Skua dive bomber. With a better engine it probably could have carried a bigger bomb, heck, just put a constant speed prop on it might have done wonders for load carrying ability. Now do a reality check and figure out the most likely target/s. The Twins and the Bismarck or the 3 pocket battleships, several heavy cruisers, 6-7 light cruisers, 20-30 destroyers plus large torpedo boats. You only need AP bombs for the first 3. AP bombs might just go right through the light cruisers and smaller.
A 1000lb bomb with 50% explosive will cause major damage to most ships if it gets through even one un-armored deck before exploding. They are very dangerous in the case of a near miss (very near) as that is as much or more explosive than many aerial torpedoes used. Damage from 5-10ft away is going to be very similar to a torpedo hit.
You can't really plan on it but it does increase the target area a bit.