Those prices seem ok. But I would also think about and possibly factor in:
The price of the thread...which you may need to buy...and it may have trimbands.
Will you need color preserver? The epoxy...maybe even two coats.
The mixing cup(s)...the brush(es)...the clean up (acetone).
Then if you have to take a guide off...a guide with out color preserver (epoxy only) will take a little more time.
If your trying to make a living out of rod building...dont sell your self short.
Keep up with your time and material and then ask yourself...is $5 enough?
The cost to do 1 guide that needs two coats and color preserver:
2 brushes: $0.20 (maybe use a reusable brush...but you still have to clean it)
Color preserver: The acrylic stuff will last forever...but I personally dont like it and use a lacquer kind with may last...or it may evaporate on ya. (skipping cost)
Epoxy. Say you buy FlexCoat Wrap kit with Syringes. 2oz Hardner 2oz Resin @ $15.00
That would do roughly 20 batches. I mix 3ml of each component. I can do 1 guide or two whole sets of guides.
So this is almost $0.75 a batch. Now you can buy bigger bottles...and use less mix...but this is what I do.
The reason I use 3ml is to reduce a margin of error on a 1:1 mix.
Acetone is $9 a quart...about $0.30 an ounce. I will use about an ounce cleaning the syringes.
So...you can see that Im almost getting to $2 or more on supplies. (let alone the cost and time getting those supplies).
Again...this can be the cost of 1 guide...or the cost for two whole rods of guides.