Dodge Caravan '96 3.0 Airconditioner

I just started using the air conditioner in my Dodge Caravan 96 (3.0 L) . I
notice that the airconditioner clutch does NOT engage with a crisp click, rather
with a dull pop and about 50% of the times when it engages it starts producing
dull grinding sound that lasts for about a minute, then diminishes. All of this
is noticeable when the car is idling and the hood is open.

While driving with the airconditioner on, the dull grinding is felt like mild
vibration in the car and at times when stepping on gas pedal, the airconditioner
clutch/compressor produces accelration like sound (like you hear when you
disengages the vehicle clutch/transmission without lifting the foot off gas
pedal.

The airconditioner cools as it always did, so if it was the compressor going bad
then there should be no cooling or diminished cooling. If the car is driven
with the air conditioner off, none of these problems occur.

My thought is that probably the compressor clutch does not always engage
properly, and some times it does because the problem is intermittent ?

Could someone kindly comment on my observations, if my thoughts are logical?

Is the clutch considered a separately replaceable part or both the clutch and
compressor will need to be replaced ? I would be able to do it myself, so any
ball park idea for the cost?

Tia

Matt