Adds some of the new Frontiersmen weapons to the Black Market (#3332)

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## About The Pull Request

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documented or this can delay review and even discourage maintainers from
merging your PR! -->

Adds the Mauler, Spitter and Pounder and their respective magazines to
the Black Market

## Why It's Good For The Game

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benefit the game. If you can't justify it in words, it might not be
worth adding. -->

They're illicit, pirate weapons, and the Spitter itself was made in mind
for black market usage in it's descriptions, so they're fitting
additions to the black market, and gives these interesting weapons a
place to be bought and seen.

## Changelog

:cl:
add: Adds the Mauler, Spitter, and Pounder to the black market
/:cl:

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code/modules/cargo/blackmarket/blackmarket_items/ammo.dm

@@ -230,3 +230,34 @@
 	stock_max = 5
 	availability_prob = 0
 
+/datum/blackmarket_item/ammo/mauler_mag
+	name = "Mauler Magazine"
+	desc = "A 12 round 9mm magazine for the Mauler Machine Pistol."
+	item = /obj/item/ammo_box/magazine/m9mm_mauler
+	price_min = 250
+	price_max = 750
+	stock_min = 3
+	stock_max = 5
+	availability_prob = 0
+
+/datum/blackmarket_item/ammo/spitter_mag
+	name = "Spitter Magazine"
+	desc = "A 30 round 9mm magazine for the Spitter submachine gun."
+	item = /obj/item/ammo_box/magazine/spitter_9mm
+
+	price_min = 250
+	price_max = 750
+	stock_min = 2
+	stock_max = 5
+	availability_prob = 0
+
+/datum/blackmarket_item/ammo/pounder_mag
+	name = "Pounder Pan Magazine"
+	desc = "A 50 round pan magazine for the Pounder submachine gun. Heavy enough to double as an emergency melee weapon to beat off your enemies in a pinch."
+	item = /obj/item/ammo_box/magazine/c22lr_pounder_pan
+
+	price_min = 400
+	price_max = 750
+	stock = 2
+	availability_prob = 0
+

code/modules/cargo/blackmarket/blackmarket_items/weapons.dm

@@ -304,6 +304,40 @@
 	stock = 2
 	availability_prob = 30
 
+/datum/blackmarket_item/weapon/mauler
+	name = "Mauler Machine Pistol"
+	desc = "This gun's got teeth! Twelve 9mm teeth to be exact. Hardly a full smile, and you'll be losing the rest pretty quick with this thing's rate of fire."
+	item = /obj/item/gun/ballistic/automatic/pistol/mauler
+	pair_item = list(/datum/blackmarket_item/ammo/mauler_mag)
+
+	price_min = 1000
+	price_max = 2000
+	stock_max = 3
+	availability_prob = 50
+
+/datum/blackmarket_item/weapon/spitter
+	name = "Spitter Submachine Gun"
+	desc = "The aptly named Spitter won't be hitting anything outside of spitting distance. Anything in that range on the otherhand? Let's just say the bereaved will be wanting a closed casket funeral. Chambered in 9mm."
+	item = /obj/item/gun/ballistic/automatic/pistol/spitter
+	pair_item = list(/datum/blackmarket_item/ammo/spitter_mag)
+
+	price_min = 1500
+	price_max = 2250
+	stock_min = 1
+	stock_max = 2
+	availability_prob = 30
+
+/datum/blackmarket_item/weapon/pounder
+	name = "Pounder Submachine Gun"
+	desc = "There's a certain quality to quantity. With a massive 50 round capacity, this .22lr submachine is capable of laying down an jawdropping amount of fire."
+	item = /obj/item/gun/ballistic/automatic/smg/pounder
+	pair_item = list(/datum/blackmarket_item/ammo/pounder_mag,/datum/blackmarket_item/ammo/himehabu_box)
+
+	price_min = 1500
+	price_max = 2000
+	stock = 1
+	availability_prob = 35
+
 /datum/blackmarket_item/weapon/polymer
 	name = "Polymer Survivor Rifle"
 	desc = "A slapdash rifle held together by spite, dreams and a good helping of duct tape. Chambered in 7.62x40mm CLIP."