This should only give you a catalog of the available simple products that are in stock.
$products = Mage::getModel('catalog/product')->getCollection(); $products->addAttributeToFilter('status', 1); // enabled $products->addAttributeToFilter('type_id', 'simple'); //$products->addAttributeToFilter('sku', array('1234')); //for testing purposes $products->addAttributeToSelect('*'); Mage::getSingleton('catalog/product_status')->addSaleableFilterToCollection($products); Mage::getSingleton('cataloginventory/stock')->addInStockFilterToCollection($products); $prodIds = $products->getAllIds();
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