For the cape of the mountebank we would need the Dimension Door spell:
Dimension Door
Move Space 9/Gen 0
Total MP: 9
Range: Touch
Duration: One Minute
With this spell, the caster can teleport up to 800 ft. without any error.
Costs: 7 MP teleport range, 2 MP precise.
The formula is: 9 x 9 x 2000 / 5 gp = 32,400 gp. The core item costs 10,080 gp, which means that the EoMR variant has the triple cost (and you can't even take someone else with you).
The ring of Universal Elemental Immunity cost in core 2,160,000 gp. For this we need this spell:
Universal Energy Immunity
Abjure Force 15/Gen 1
Total MP: 16
Range: Touch
Duration: 1 hour
You have against all elements full protrection.
Costs: 1 MP discounted duration, 15 MP abjure force element immunity.
The formula for this type of magic item is: 16 x 16 x 1000 gp = 256,000 gp. That is 1/8th of the core item cost.
Unless someone runs all the numbers, it can't be assessed, which kind of items is cheaper or more costly in EoMR.