I spent the years 1978-2002 in the Army Reserve, and the answer is perhaps not, but it depends.
Generally speaking Reserve Component units (and here I am using the term to include the US Army Reserve and the Army National Guard)lag behind the Active Component when it comes to the fielding of most equipment. That will vary depending on the kind of equipment you're talking about (especially combat vehicles) as well as the "readiness level" of the unit, which generally amounts to how high up on the call up list the unit is .
And another thing to consider is that if you're talking about "combat arms" units (Infantry, Armor and Field Artillery) while there were combat arms units allocated to the USAR, the largest percentage of combat arms units not on active duty were in the National Guard, and after about 1993 or so ALL combat arms units in the "Reserve Components" were allocated to the National Guard.
If you're talking about Combat Support or Combat Service Support, that is the "bread and butter" for the USAR, and depending on the type of unit, a large percentage or in a few cases ALL of the Army's units of this type are in the Reserve Components, and so there MIGHT be a chance that a Reserve unit is the only type which gets certain stuff and so they have the latest gear.
But as a rule of thumb, it's safe to say that a US Army Reserve combat arms unit would almost certainly lag the active component in terms of issued equipment, by several years and given the political clout of the National Guard, would likely be somewhat behind the Guard as well.
As far as a site to find definitive information, you'd really have to go to a specific unit's website to see if it had historical information, and if it's a combat arms unit that WAS in the USAR during this period, they have all been inactivated so there may not be much information out there.
For what it's worth, the 4/20 FA Bn was a USAR unit which inactivated in August of 1993. We were equipped with the M110A2 8" SP howitzer and I'm pretty sure our equipment was every bit as up to date as the 1/182 which is in the Michigan Army National Guard.