You could find more modern fixtures, but the efficiency would not be much better. These do 62 lumens/watt OTF (including driver and optics losses) which is right around what most fixtures like this do. You might see 75 lumens/watt out of one of the latest fixtures.
I have bought several 5000 lumen/80 watt fixtures and 10,000 lumen/150 watt street lights from them and they seem to work quite well. They did not appear to be used, or were slightly used (i.e. no dust/dirt/scratches) Most of what they sell seem to be store returns, demo units, and old stock items.
Most of my house is lit with bulbs (over 300 of them) I bought from them. They all tested at or above the manufacturers specs. I bought them at prices that were very close to what halogens would have cost: My adventures in LED home lighting
I did have to have around half of the PAR20 bulbs (around 80 bulbs) replaced because of a recall… so those are all new bulbs now.