External handrail fixing

Suitable L shaped bracket bolted to the wall, to give you a place to bolt the foot of the "off the shelf" unit?

Or (to paraphrase Brad Paisley)

Get you a welder, learn how to weld

One quite nice thing about resin fixings is that you can use custom lengths of threaded rod, to get more load capacity. With a wide baseplate you can shift most of the loading to tension on the bolts - and resin bonded anchors are good at dealing with that.

I would not be too worried about that; quarry tiles are hard but drillable - normally something like a Bosch multi material bit will work. If you find it difficult, then one of the miniture grit edges hole saws will do it (they will do porcelain - which is the hardest tile to cut IME).

If you are handy with a welder, then you can buy all the various bits of wrought iron metalwork for handrails separately and make what you need.