curl --request GET \
  --url https://api.pingproxies.com/1.0/public/user/checkout/catalog \
  --header 'X-API-Private-Key: <api-key>' \
  --header 'X-API-Public-Key: <api-key>'

{
  "data": {
    "datacenter_us": {
      "country_id": "us",
      "product_cycle_options": [
        "1:month",
        "3:month",
        "1:year"
      ],
      "product_is_available": true,
      "product_is_per_ip": true,
      "product_name": "Datacenter Proxies [US]",
      "product_protocol": "ipv4",
      "product_stock": 10,
      "product_type": "datacenter"
    },
    "isp_gb": {
      "country_id": "gb",
      "product_cycle_options": [
        "1:month",
        "3:month",
        "1:year"
      ],
      "product_is_available": true,
      "product_is_per_ip": true,
      "product_name": "Static Residential ISP Proxies [GB]",
      "product_protocol": "ipv4",
      "product_stock": 181,
      "product_type": "isp"
    }
  },
  "message": "Checkout catalog successfully retrieved."
}