@McTag,
Ok..that could help me narrow it down for you. I just want to ascertain for your sake that you don't just need a sturdy better newer pair that are reasonable. High fidelity and higher price often go together...but I don't want to glaze you over if that's not of your main concerns.
Some listening room questions:
Do you hear fairly well orchestral or jazz music in real life at a live concert or when you play or listen to a small group or as a musician? Do you hear your speakers in living room fairly well? How is your hearing relative to say your wife or another listener? Does she shrink her nose up when you contour the music to suit you (besides the louder volume)?
So, what might need qualifying is whether or not your hearing loss is uniformly distributed or tending (like many of us 'mature' males) to have a notch missing from the high frequencies? Typically us over-'60s, or urban dwellers who may have heard loud music or industrial noise with regularity, are missing just beyond, say the 10khz mark.
However, let's move on past this for a moment and assume you're just loss of hearing is distributed uniformly across the audio spectrum - e.g - hearing music only with a lower volume issue.
Specs
I wouldn't focus on the resistance spec as much as the sensitivity spec. I'll explain:
Let's assume your old Sony's were sensitive in the range of sound pressure level of 92-96 db when driven by a 1 watt signal. That is considered relatively easy demand on the amp and moderate-to-very full sounding sound pressure or volume level to the ear. Whereas many of new designs are sensitive to the level of 96 db level when driven by 1 watt, that is far better than say 90-92 db. FYI, because db are a logarithmic measure, 3 db is heard as a doubling of volume. so, 96 db is awesome, 92 dBs is decent ..whereas with a 90 dB pair, you could perceive as perhaps too soft. Get the drift?
Anyhow, as I sift through the specs (if they're accurate), I can name a few that are quite sensitive. But I'll let you steer me with answers so I am not wasting your time or glazing you over.
{edit: academic research on hearing loss indicates some notable high freq loss over age 60 at around 6-8 khz, not as I wrote earlier at the band above 10khz: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2802451/ }