Hey I found out that there wasn't a super rare price list so I decided to make one for you guys. The list may be inaccurate, The prices would be in shells.

Change Logs
13 Sept 2013: Added crab daggers to the list
14 Sept 2013: Corrected pricing of Trashpicks
15 Sept 2013: Added La Chancla



Trashpicks
Syringe ~ 7-8k
Cigar ~ 8-10k
Pencil ~ 10-12k
Plunger ~ 14-16k
Spear ~ 15-16k
Thermometer ~ 15-17k
Bone ~ 16-17k
Paintbrush ~ 16-18k
Pen ~ 17-19k
Skateboard Trashpick ~ 30-34k
Rainbow Skateboard Trashpick ~ 65-70k

Umbrellas
Black Umbrella ~ 21-22k (dropping)
Green Umbrella ~ 46k (confirmation needed)
Pink Umbrella ~ (???)
Blue Umbrella ~ (???)
Red Umbrella ~ (???)
White Umbrella ~ (???)
Jeni's Umbrella ~ 46-56k
Orange Umbrella ~ (???)
Purple Umbrella ~ (???)
Golden Umbrella ~ (???)
Rainbow Umbrella ~ (???)

There are very few coloured umbrellas selling in the market for shells, thus information would need to be added at a later date.

Candy Melees
Vanilla Ice Cream ~ 8-10k
Chocolate Dagger ~ 12-14k
Marshmallow Dagger ~ 14-16k

Flags
M4M ~ 500-600
SnK ~ 550-650
Jatz ~ 600-800
SPD ~ 600-800
Small USA ~ 200-300
German ~ 2-3k (confirmation needed)
Lebanese ~ 2-3k (confirmation needed)

Hammers & Axes
Heart Axe ~ 5-6k
Graalians Hammer ~ 14-16k
Bunny Hammer ~ 15-17k
Toy Hammer ~ 18-22k (confirmation needed)
Taco Hammer ~ (???)
Panda Hammer ~ 70-100k
Pepper Pickaxe ~ 18-20k
Pickaxe ~ 70-100k

Others
Sham Sword ~ 600-700
Clover ~ 1.4-1.6k
Sham Dagger ~ 1.8-2.4k
Zanmato ~ 2.2-2.8k
Taser ~ 3.6-4.2k (dropping)
Chaplain ~ 50-60k
Red Drag ~ (???)
Green Drag ~ (???)
La Chancla ~ 50k
Pink Sapphire Dagger ~ 12-15k
Ice Blade ~ 15-16k (tendency to drop)
Noob Trident ~ (???)
HW Dagger ~ (???)

Items
Egg Hacky ~ 100-200
Egg Dance ~ 100-200
Toy Bat ~ 2-3k
Skull Juggle ~ 2.5-3.5k
Super Fart ~ 4-5k
SPD Fart ~ 6-7k
Panda Hug ~ 3-4k
HW Wand ~ 14-18k
Droppable Hat ~ (???)
Mushroom Knife ~ (???)
Golden Flower Basket ~ (???)
Zombie Morph ~ (???) It is freaking cool, sadly I only saw it once
Golden Katana ~ Priceless (Thank you Jester ^^)
Flamecrow Wings ~ (???)

Crab Daggers
Red ~ 200-250
Yellow ~ 100-200
Green ~ 100-200
Blue ~ 100-200
Black ~ 100-200


Disclaimer of Liability
Nezo shall not be held liable for any improper or incorrect use of the information described and/or contained herein and assumes no responsibility for anyone's use of the information. In no event shall Nezo be liable for any direct, indirect, incidental, special, exemplary, or consequential damages (including, but not limited to: procurement of substitute goods or services; loss of use, data, or profits; or business interruption) however caused and on any theory of liability, whether in contract, strict liability, tort (including negligence or otherwise), or any other theory arising in any way out of the use of this infomation, even if advised of the possibility of such damage. This disclaimer of liability applies to any damages or injury, whether based on alleged breach of contract, tortious behavior, negligence or any other cause of action, including but not limited to damages or injuries caused by any failure of performance, error, omission, interruption, deletion, defect, delay in operation or transmission, computer virus, communication line failure, and/or theft, destruction or unauthorized access to, alteration of, or use of any record.

Thank you